In our daily life, preform molds are widely used in multi-packaging industries such as edible oil, beverage, candy, and medicine.
The concept of preform mold
The preform mold is a molding method in which the molten material is injected into the mold by an injection machine to form the mold, and then the parison is placed in the blow mold while it is hot, and air is introduced to inflate the parison.
The components of the preform mold
The injection mold is mainly composed of three parts: gating system, molding parts and structural parts. Among them, the gating system and the molding parts are the parts that are in direct contact with the plastic, and are the most complex, the most variable parts of the mold, and the parts that require the highest machining accuracy.
The principle of preform mold
Feed the powder or granular plastic from the hopper of the injection machine into the heated barrel; after heating, melting and plasticizing, the material will be compressed and moved forward with the help of the thrust of the plunger or screw, through the nozzle at the front of the barrel, to It is injected into the cavity of the closed mold with a low temperature at a fast speed; after a certain period of cooling and setting, the mold is opened to obtain the product.
The advantages of preform mold
Preforms will largely determine the quality of plastic bottles, and the importance of plastic bottles is self-evident. The functions of the injection molding machine mainly include: being able to install a mold of a given size, providing sufficient clamping force, operating according to the requirements of the cycle time, and plasticizing enough materials.
Several aspects to pay attention to when choosing a preform mold
1. Product weight: Products of different weights have different requirements for the hot runner.
2. Cycle cycle: The fast production cycle means that the requirements for the nozzle will be very high.
3. Gate: In order to maintain a good thermal balance in each molding cycle, the tip of the heat flow nozzle must have the function of melting the material and cooling the seal.
4. Nozzles: Nozzles can be distinguished by size, temperature distribution, physical properties, materials used, ease of maintenance, and price.
5. Runner: The use of hot runner system not only saves raw materials, but also saves the process of removing the handle by hand, machinery or other methods in the past.
6. Product design: In order to ensure a smooth product appearance at the end of molding, those factors must be considered in its structural design.
7. Temperature control: Each nozzle must be connected with a relatively complex temperature controller.